river/river/View.zig
Isaac Freund 96a91fd2f7 view: double buffer focus, use counter not bool
- Double buffering focus state ensures that border color is kept in sync
with the transaction state of views in the layout.
- Using a counter instead of a bool will allow for proper handling of
multiple seats. This is done in the same commit to avoid more churn in
the future.
2020-08-03 18:54:18 +02:00

375 lines
12 KiB
Zig

// This file is part of river, a dynamic tiling wayland compositor.
//
// Copyright 2020 Isaac Freund
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
const Self = @This();
const build_options = @import("build_options");
const std = @import("std");
const c = @import("c.zig");
const log = @import("log.zig");
const util = @import("util.zig");
const Box = @import("Box.zig");
const Output = @import("Output.zig");
const Root = @import("Root.zig");
const ViewStack = @import("view_stack.zig").ViewStack;
const XdgToplevel = @import("XdgToplevel.zig");
const XwaylandView = if (build_options.xwayland) @import("XwaylandView.zig") else @import("VoidView.zig");
pub const Constraints = struct {
min_width: u32,
max_width: u32,
min_height: u32,
max_height: u32,
};
// Minimum width/height for surfaces.
// This is needed, because external layouts and large padding and border sizes
// may cause surfaces so small, that bugs in client applications are encountered,
// or even surfaces of zero or negative size,which are a protocol error and would
// likely cause river to crash. The value is totally arbitrary and low enough,
// that it should never be encountered during normal usage.
pub const min_size = 50;
const Impl = union(enum) {
xdg_toplevel: XdgToplevel,
xwayland_view: XwaylandView,
};
const State = struct {
/// The output-relative coordinates and dimensions of the view. The
/// surface itself may have other dimensions which are stored in the
/// surface_box member.
box: Box,
/// The tags of the view, as a bitmask
tags: u32,
/// Number of seats currently focusing the view
focus: u32,
float: bool,
fullscreen: bool,
};
const SavedBuffer = struct {
wlr_client_buffer: *c.wlr_client_buffer,
box: Box,
transform: c.wl_output_transform,
};
/// The implementation of this view
impl: Impl,
/// The output this view is currently associated with
output: *Output,
/// This is non-null exactly when the view is mapped
wlr_surface: ?*c.wlr_surface,
/// The double-buffered state of the view
current: State,
pending: State,
/// The serial sent with the currently pending configure event
pending_serial: ?u32,
/// The currently commited geometry of the surface. The x/y may be negative if
/// for example the client has decided to draw CSD shadows a la GTK.
surface_box: Box,
/// The geometry the view's surface had when the transaction started and
/// buffers were saved.
saved_surface_box: Box,
/// These are what we render while a transaction is in progress
saved_buffers: std.ArrayList(SavedBuffer),
/// The floating dimensions the view, saved so that they can be restored if the
/// view returns to floating mode.
float_box: Box,
draw_borders: bool,
pub fn init(self: *Self, output: *Output, tags: u32, surface: var) void {
self.output = output;
self.wlr_surface = null;
self.current = .{
.box = .{
.x = 0,
.y = 0,
.height = 0,
.width = 0,
},
.tags = tags,
.focus = 0,
.float = false,
.fullscreen = false,
};
self.pending = self.current;
self.pending_serial = null;
self.saved_buffers = std.ArrayList(SavedBuffer).init(util.gpa);
self.draw_borders = true;
if (@TypeOf(surface) == *c.wlr_xdg_surface) {
self.impl = .{ .xdg_toplevel = undefined };
self.impl.xdg_toplevel.init(self, surface);
} else if (build_options.xwayland and @TypeOf(surface) == *c.wlr_xwayland_surface) {
self.impl = .{ .xwayland_view = undefined };
self.impl.xwayland_view.init(self, surface);
} else unreachable;
}
pub fn deinit(self: Self) void {
for (self.saved_buffers.items) |buffer| c.wlr_buffer_unlock(&buffer.wlr_client_buffer.*.base);
self.saved_buffers.deinit();
}
pub fn needsConfigure(self: Self) bool {
return switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.needsConfigure(),
.xwayland_view => |xwayland_view| xwayland_view.needsConfigure(),
};
}
pub fn configure(self: Self) void {
switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.configure(),
.xwayland_view => |xwayland_view| xwayland_view.configure(),
}
}
pub fn sendFrameDone(self: Self) void {
var now: c.timespec = undefined;
_ = c.clock_gettime(c.CLOCK_MONOTONIC, &now);
c.wlr_surface_send_frame_done(self.wlr_surface.?, &now);
}
pub fn dropSavedBuffers(self: *Self) void {
for (self.saved_buffers.items) |buffer| c.wlr_buffer_unlock(&buffer.wlr_client_buffer.*.base);
self.saved_buffers.items.len = 0;
}
pub fn saveBuffers(self: *Self) void {
if (self.saved_buffers.items.len > 0) {
log.err(.transaction, "view already has buffers saved, overwriting", .{});
self.saved_buffers.items.len = 0;
}
self.saved_surface_box = self.surface_box;
self.forEachSurface(saveBuffersIterator, &self.saved_buffers);
}
fn saveBuffersIterator(
wlr_surface: ?*c.wlr_surface,
surface_x: c_int,
surface_y: c_int,
data: ?*c_void,
) callconv(.C) void {
const saved_buffers = util.voidCast(std.ArrayList(SavedBuffer), data.?);
if (wlr_surface) |surface| {
if (c.wlr_surface_has_buffer(surface)) {
saved_buffers.append(.{
.wlr_client_buffer = surface.buffer,
.box = Box{
.x = surface_x,
.y = surface_y,
.width = @intCast(u32, surface.current.width),
.height = @intCast(u32, surface.current.height),
},
.transform = surface.current.transform,
}) catch return;
_ = c.wlr_buffer_lock(&surface.buffer.*.base);
}
}
}
/// Set the pending state, set the size, and inform the client.
pub fn setFullscreen(self: *Self, fullscreen: bool) void {
self.pending.fullscreen = fullscreen;
if (fullscreen) {
// If transitioning from float -> fullscreen, save the floating
// dimensions.
if (self.pending.float) self.float_box = self.current.box;
const output = self.output;
self.pending.box = Box.fromWlrBox(
c.wlr_output_layout_get_box(output.root.wlr_output_layout, output.wlr_output).*,
);
self.configure();
} else if (self.pending.float) {
// If transitioning from fullscreen -> float, return to the saved
// floating dimensions.
self.pending.box = self.float_box;
self.configure();
} else {
// Transitioning to layout, arrange and start a transaction
self.output.root.arrange();
}
switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.setFullscreen(fullscreen),
.xwayland_view => |xwayland_view| xwayland_view.setFullscreen(fullscreen),
}
}
/// Move a view from one output to another, sending the required enter/leave
/// events.
pub fn sendToOutput(self: *Self, destination_output: *Output) void {
const node = @fieldParentPtr(ViewStack(Self).Node, "view", self);
self.output.views.remove(node);
destination_output.views.push(node);
self.output.sendViewTags();
destination_output.sendViewTags();
c.wlr_surface_send_leave(self.wlr_surface, self.output.wlr_output);
c.wlr_surface_send_enter(self.wlr_surface, destination_output.wlr_output);
self.output = destination_output;
}
pub fn close(self: Self) void {
switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.close(),
.xwayland_view => |xwayland_view| xwayland_view.close(),
}
}
pub fn forEachSurface(
self: Self,
iterator: c.wlr_surface_iterator_func_t,
user_data: ?*c_void,
) void {
switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.forEachSurface(iterator, user_data),
.xwayland_view => |xwayland_view| xwayland_view.forEachSurface(iterator, user_data),
}
}
/// Return the surface at output coordinates ox, oy and set sx, sy to the
/// corresponding surface-relative coordinates, if there is a surface.
pub fn surfaceAt(self: Self, ox: f64, oy: f64, sx: *f64, sy: *f64) ?*c.wlr_surface {
return switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.surfaceAt(ox, oy, sx, sy),
.xwayland_view => |xwayland_view| xwayland_view.surfaceAt(ox, oy, sx, sy),
};
}
/// Return the current title of the view. May be an empty string.
pub fn getTitle(self: Self) [*:0]const u8 {
return switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.getTitle(),
.xwayland_view => |xwayland_view| xwayland_view.getTitle(),
};
}
/// Clamp the width/height of the pending state to the constraints of the view
pub fn applyConstraints(self: *Self) void {
const constraints = self.getConstraints();
const box = &self.pending.box;
box.width = std.math.clamp(box.width, constraints.min_width, constraints.max_width);
box.height = std.math.clamp(box.height, constraints.min_height, constraints.max_height);
}
/// Return bounds on the dimensions of the view
pub fn getConstraints(self: Self) Constraints {
return switch (self.impl) {
.xdg_toplevel => |xdg_toplevel| xdg_toplevel.getConstraints(),
.xwayland_view => |xwayland_view| xwayland_view.getConstraints(),
};
}
/// Find and return the view corresponding to a given wlr_surface, if any
pub fn fromWlrSurface(wlr_surface: *c.wlr_surface) ?*Self {
if (c.wlr_surface_is_xdg_surface(wlr_surface)) {
const wlr_xdg_surface = c.wlr_xdg_surface_from_wlr_surface(wlr_surface);
if (wlr_xdg_surface.*.role == .WLR_XDG_SURFACE_ROLE_TOPLEVEL) {
return util.voidCast(Self, wlr_xdg_surface.*.data.?);
}
}
if (build_options.xwayland) {
if (c.wlr_surface_is_xwayland_surface(wlr_surface)) {
const wlr_xwayland_surface = c.wlr_xwayland_surface_from_wlr_surface(wlr_surface);
return util.voidCast(Self, wlr_xwayland_surface.*.data.?);
}
}
return null;
}
/// Called by the impl when the surface is ready to be displayed
pub fn map(self: *Self) void {
const root = self.output.root;
log.debug(.server, "view '{}' mapped", .{self.getTitle()});
// Add the view to the stack of its output
const node = @fieldParentPtr(ViewStack(Self).Node, "view", self);
self.output.views.push(node);
// Focus the new view, assuming the seat is focusing the proper output
// and there isn't something else like a fullscreen view grabbing focus.
var it = root.server.input_manager.seats.first;
while (it) |seat_node| : (it = seat_node.next) seat_node.data.focus(self);
c.wlr_surface_send_enter(self.wlr_surface.?, self.output.wlr_output);
self.output.sendViewTags();
if (self.pending.float) self.configure() else root.arrange();
}
/// Called by the impl when the surface will no longer be displayed
pub fn unmap(self: *Self) void {
const root = self.output.root;
log.debug(.server, "view '{}' unmapped", .{self.getTitle()});
// Inform all seats that the view has been unmapped so they can handle focus
var it = root.server.input_manager.seats.first;
while (it) |node| : (it = node.next) {
const seat = &node.data;
seat.handleViewUnmap(self);
}
self.wlr_surface = null;
// Remove the view from its output's stack
const node = @fieldParentPtr(ViewStack(Self).Node, "view", self);
self.output.views.remove(node);
self.output.sendViewTags();
// Still need to arrange if fullscreened from the layout
if (!self.current.float) root.arrange();
}
/// Destory the view and free the ViewStack node holding it.
pub fn destroy(self: *const Self) void {
self.deinit();
const node = @fieldParentPtr(ViewStack(Self).Node, "view", self);
util.gpa.destroy(node);
}